Combined telephone and alarm system.



'PATENTED JULY 10, 1906.

3. GI WEBSTER. v QOMfBINEDTELEPHONE ANDYALARMISYSTEM= APPLICATION FILED APR. 26, 1904. I

' 11 SHEETS-SHEET 1.

No. 825,623. PATEQNTEDJULYI 10, 1906] H. G. WEBSTER.

COMBINED TELEPHONE AND ALARM SYSTEM.

APPLICATION FILED APB..2E,1904. I

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A 31 3 l 1 v I Fl 'i i 05 E 53 E :mIT M I 43 MA /w PATENTED JULY 10, 19(16;

H. G. WEBSTER.

COMBINED TELEPHONE AND ALARM SYSTEM.

APPLICATION FILED APR. 26. 1904.

I 11 SHEETS-SHEET 4.

No. 825,623. PATENTED JULY 10, 1906 H. G. WEBSTER.

COMBINED TELEPHONE AND ALARM SYSTEM.

' APPLICATION IILED'APR. 26, 1904.

' 11 SHEETS-SHEET 5.

(Mffiissss: f I I 4 225277202;

PATENTED JULY 10, 1906.

HQG. WEBSTER. I COMBINED TELEPHONE AND ALARM SYSTEM.

APPLICATION FILED APR. 28, 1904.

11 snnms-sxnm k.

PATENTED JULY 10, 1906.

H. G. WEBSTER. COMBINED TELEPHONE AND, ALARM SYSTEM.

APPLICATION IILED APR. 26, 1904.

11 annua -SHEET 1.

PATENTED JULY 10, 1906.

I H. G. WBBSTEILa COMBINED TELEPHONE AND ALARM SYSTEM APPLICATION FILED APR. 26, 1904.

11 snnnmssnnirr a.

R wm l m H M-m h m s w 0 M I V 7m I No. 825,623. PATENTED JULY 10, 1906.

E H. G, WEBSTER-H COMBINED TELEPHONE AND ALARM SYSTEM."

APPLICATION FILED APR. 26, 1904.

11 SHEETS-SHEET 9,

. HJIIIIL F No. 825,623. PATENTED JULY 10, 1906.v

- H. e. WEBSTER.

COMBINED TELEPHONE AND ALARM SY STEM.

. APPLICATION PILVED APR. 26, 1904.

and??? 22 2 ephone-Exchange and Alarm System, of

HARRY G. WEBSTER, OF OHICAGQ, ILLINOIS, ASSIGNOR KELLOGG, OF CHICAGO, ILLINOIS.

COMBINED TELEPHONE AND LARM s'YsTEM;

Specification of Letters Patent.

Patented Julv 10. 1906.

Application filed April 26. 1904. Serial No. 204,978.

T0' 1,ZZ whom it may concern:

Be it known that I, HARRY G. WEBSTER, a citizen of the United States of America, and a resident of. Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in a Combined Telwhich the following is a specification. 7

My invention relates to systems in which telephone circuits extendin from a telephone exchange to subscribers stations adapted to be interconnected for conversation are also utilized for the transmission of fire, burglar, or other alarm-signals. It is evident that when such telephone-circuits can be successfully utilized for alarm-signaling, as well as for telephone-exchange service, great econv omy in construction and maintenance may be eflected over arrangements in which separate circuits are used for the two classes of service. Numerous plans have been proposed for such combined systems, but 'nonein which the necessary requirements of each class of iervice, as hereinafter stated, are provided The object of my invention is to provide a system in which the necessary conditions for each classof service shall be at all times maintained, particularly intheir relations each to the other. In such a system, while the circuitis seldom used for. transmitting alarm-signals, it is necessary that it shoul always be in readiness for such use, and such a signal when transmitted must reach its ounded or crossed.

esirable, if not absolutely necessary, that the proper alarm-receiving station without error or loss of time. It is also necessary that the alarm-receiving station should receive an immediate indication in case the circuit-wires become broken or en, and preferably that such an indication e given 1f they become It is also eminently alarm-signal be recorded or permanently maintained at the alarm-receiving. station until acted upon by the alarm operator. Finally,the' circuit and an aratus must be adapted for the successfu transmission of I telephonic signals and speech, except when actually in use in giving an alarm-signal, during Wl'llCl] time anyinterference with its telephonic'service may be disregarded.

My invention is made to meet the above conditions and it consists, briefly, in the combination of a telephone-exchange, a. source of circuit except when interrupted by the alarm-sending apparatus.

In the preferred embodiment of my invention I employ in connection with a commonbattery telephoneexchange means by which the line-circuit is normally-closed through a. high resistance or impedance located in th bridge of the circuit at the substation or intermediate of the subscriber's telephone and. thepoint at which the alarm-sending apparatus is associated with the line. Thisresistance or im edance, while allowing sufficientcurrent to ow to preserve the normal condi 'tion' of the alarm-receiving apparatus, is sufficiently highto prevent a normal currentflow which would interfere with the operation of the telephone-signals and is so de--' signed and connected as to avoid interference with the transmission of speech. The alarmreceiving-apparatus consists, preferably, of a special relay associated with the line-Controlhnglocal-ci'rcuit apparatus to indicate or record the alarm signal and so designed and adjusted as to attract its armature when energized by any current equal to or greater than the normal current-flow or by the'alter- .aating current used in calling subscribers. Such relays arewell known, one type 'being that having a heavy armature retracted by gravity and which, as it does not depend upon spring-tension for its retraction, will not break contact through an instantaneous opening of its circuit, as might occur in making a tele hone switch connection. This relay may e connected from ground (or from the grounded side of the central battery) to the correspondmgside of the line-circuit,and

in such case wou d be of such resistance and. impedance as tobest adapt it to the particular telephone-exchange circuit with which'it is associated. -An alternative arrangement would be to connect this special relay serially in the circuit, preferably in that side connect ed with the grounded side of thesentral battery, although it might be-placed iirthe other side of the circuit by sacrificing some of the advantages of the other connection. The

serially-included relay would he necessarily so designed and connected as to present little or no impedance to'voice-cur'rents nor resistance to' the direct'cu'rren't required for oper- 'those'having a copper shell or shunted by a condenser or by a non-inductive winding. It

is 'to be notedfthat the special-relay ma be i loated at the telephone-exchange, although as the rest of the alarm-receivin when desirable it may beat the same location apparatus.

. It will also be seen that, while al of the lines of: a telephone system might be wired for the conneotlonof the special alarm apparatus, in

practice only certain ofthe lines will have thisapparatus, and these'lines will not be coned necessarily to any particular group,

' but will bescattered throughout the entire system except for such special equipment. .To this end I provide Kstem, also that it is desirable to avoid anging thenormal wiring of the telephone mes as have the means whereby, the alarm-receiving appara- "tug may be. assembled at any desired place and connections made and changed between apparatus and any lines of the telephone syst(-.i m infa's stematic and orderly manner i the telephone-exchange. 39,

*Isuchas a telegraph-register, might be con and without tering the permanent, wiring of c v It is evident that fapparatusfo'r indicating the alarm-signal,

; netted directly with the line-.circuit;-but the use; ofg a special relay is preferable,

The

" alarm-sending apparatus consists, 'referably,

of'the'iwel'l-known make-and-brea wheel or equivalent \device (such as is used'in districtmessenger b oxes)'located between the high- "resistancebridge and the.central telephone exchange and having one or both sides of the line-circuit carried through its normally closed contacts. This makesand break device, normally under. tension, may be released mannally or by an electromagnetin a local circuit or maybe of special construction to be releasedby the direct action of heat. When. so released, it will give a characteristic "number of makes and breaks, repeated sev-' eral times, indicating the particularcircuit fr'0m which the alarm comes, or it may slm- 'ply give a continuous make,- and break of 1 regular duration to indicate: simply that an open.

alarm. is being given. It is also desirable that the make-and-break wheelshall come to rest at a point which shall leave the circuit It is thus seen that my invention comprises an organization of a normal telehone-circuit system'iwith an alarm-circuit 'sy stem, in which :there is a comparatively weak but continuous direct current-flow,

which serves to preserve the normal condition of the alarm-receivingapparatus. When thiscurrent is increased or momentaril in-i tempted or an alternating current su stituted thereforin' the use of the telephone, the normal'condition of the alannereceiving apparatus is not interferedwith, In case an alarmsignal is to be transmitted, the breaking of the circuit (and consequent interruption of all current in the line) by the alarmsending aparatus, releases the armature of the special relay and transfers the signal automatically and mstantaneousl to the alarmreceiving station, which may e located adjat'ant point', and in case the circuit-wires are broken or grounded the consequent diversion of current from the circuit or interruption of all current also immediately indicates these conditions at the alarm-receiving station by the prolonged actuation of the apparatus without the characteristic signal.

In the accompanying-drawings, illustrating my invention, I have indicated the makeand-break mechanism of the alarm-sending apparatus, as M,- the special relay, as F, and the register or recording device; as R. The high resistance or impedance is shown as I;

Figure l'shows two complete line-circuits embodying my invention in a telephone-exchan e of the well-known two-wire type; in whic "the con'necting-jacks are norm all disconnected from the line, together wit regular cord connecting ap aratus. In this .figure the special relay is shown as in bridge or from the ground side of the line to ground. Fig. 2 shows one alternative arprovlde a high-resistance bridge in place of the impedance I. Fi s. 22-2, 2, 2 and 2 indicate various modlfications of the alarmfications of -the=.a1arm-receiving apparatus. Fi s. 13 .to' 18;: inclusive, showdiagram'mat- ,ica ly .several methods of arranging for the s eclal relay F'when it is to be seri'allyinc uded in the line-circuit,- Fig. 19 illustrates my invention as embodied -m a telephone system of/the well-known three-wire type, in which there is a cut-ofi relay operated over a local circuit, the special relay E bein bridged to one side of the line. Fig. 20 s ows one method of embodying m ,inventipn in that .tele' hone system normal y usin a differentiall -wound cut-ofi' relay; In this figure, as l t e1previ0us one, the special relay F is shown the cord connecting apparatus which dicate means by which the make-and-bre ak .wheelof the alarm-sending apparatus may be stop ed, after making a certainnumber of revo u'tions', at a point to leave the line-circuit open. 'Fig. 22 shows two complete line- .cir'cuits of a telephone-exchange embodying included serially in the line. This exchange is of the two-Wire ty e, in whichthe connecting-j acks are norma y disconnected from the line, and the regular cord connecting appathe cent to the telephone-exchange or at some disran'gcinentof the subscribers telephone, to

ICQ

sending apparatus over thatshown in Fig. Figs. 3 to 12, inclusive, indicate various mod1- 'IIct bridged to ground, and in both figures I have is ordinarily-employed. Figs. 21 and 21 inr my invention, in which the special relay F is v ratus is shown. Fig. -23'shows my invention having the relay F serially included in the line in the same three-wire exchange system as is shown in Fig. 19, with regular cord connecting apparatus. Fig. 24 shows the serially-included relay F inthe exchange system.

having a ditferentiall -wound cut-ofl relay.

.Figs. 25, 26, and 27 ilustrate different em .bodiments of my invention in a telephone system of that type in which there is arelay permanently connected with the line and.

, source of current and in which a three-wire circuit is used, the calling-signal and super (or coils) arepermanentl connectedinbridge visory or cord signals being located in a local circuit and controlled by the permanentlywire telephonesystems in which a line-relay,

a source of current, and an' iinpedance-coil of the line, and in which t e line-rela is'shunted by a low-wound supervisory re ay in the cord-circuit when a plug is inserted into a jack of the line Fig. 32 shows one cord-circuit regline-signal of the telephone-exc ularly employed in such a systerm Fig. 33' 7 illustrates my Invention as-embodied in a telephoneexchange system in which the line relay or signal is disconnected by separable contacts in the jacks. In this arrangement the'special relay F is in permanent brid e of the line and provides the'sole path of direct current-flow for telephone transmission and signaling. 34 indicates. a system similar to that of ig. 23, but having a specialrelay F included in that side of the line-circuit leading from the active or ungrounded side of the central battery. It is here evident that in case the line should become grounded intermediate of this relay and the contacts of the make-and-break device the only indication would be the continued dis lay of the liange, and under such a condition the relay F would not respond to an alarm-signal. Fi 35 illustrates a similar arrangement in w ich the relay F, rovlded with s ecial contact, is so arrange that it may be alanced for any given current-flow and will give a specialindication in case this flow is increased, as by a ground. or short-circuit on the line.

F1 s. 36,37, and 38 illustrate special arrangemeii ts of terminals and wiring by which the special alarm-receiving a paratus may be associated with'any of the mes of a telephone system in. a systematic and orderly manner.

Like characters refer to corresponding parts in all.of the drawings.

Referrin to the drawings, Fig. 1 illustrates my invention as embodied in one of the well-known type of central-energ or common-battery telephonesystems, in; w 'ch the subscribers can automatically signal the exchange for connection or supervision and I 1 ground through the in which the current for voice transmission and for signaling is supplied from a central source of current located at theexchange.

Considered first as a telephone system it corresponds in operative result to all of the exchange systems illustrated in the other drawin s, and its description will ap 1y equally we 1 to the others in so'faras it re ates to the "former resting normally against contacts 3 and the latter. against contact 4. Contact 4 is connected bywire 28 through the individ! ual line-rela Z to the un rounded or active side of the attery C." ontact 3 of those linesv which are not equipped with the special alarm ap aratus is 'connected directl to the grounded side of the battery. en the special alarm apparatus is used,.this groundpath may includethe resistance r or may be omitted entirel in which case the; circuit of the line won (1 be normally completed to relay F. At the su station the usual microphone sfl'receiver s and hook-switch s are provided, and the bell s withcondenser s, is permanently connected in bridge of the the circuit. The-impedance-coil I an contacts a a of the make-and break' mechanism M are only present in such lines as permanently-connected IOO have the special-alarm equipment, and as they have no eifect up'on the normal opera tion of the telephone s stem they will be for the present disregarde The switch-hook s. is adapted when the receiver is removed therefrom to engage contacts, which is con- ,nected with the microphone and'telephone receiver. The springs 1 2 carry armatures adapted to be attracted b the relay I when it is .ener ized, and this re ay has its winding 7 connecte at one side to ground andat the other side to contact-5. The contact 5 is connected with-the sleeves 7", and the contact 6 with the s rings y' of the connectionterminals j j. e line-relay! is adapted whenenergized to close b its contacts 7 the circuit of the line signalamp 1, which'circuit is completed from-battery C through the relay Z" and contacts 7 to ground.

ilot lhis pilot=relayiscommon to all lines whose lamp-signals appear in front of any one operator and has contacts 8, adapted when it is energized to close the circuit of the pilotlamp Z which is likewise common to all of the line-lamps atone operators'position.

The circuit of this pilot-lamp l 'is completed from battery (I through contacts 8 r through condenser d and relay Z to ground. Relaylis a nightbell relay common to the entire exchange and is rovided with contacts 9, adapted to close t 1e local circuit of the night-bell Z when the relay is excited. S witch-contacts' 10 are provided to short-circuit this'relay when the nightbell indication is not required. The answering-plu p is provided with a tip p and a sleeve p he former bein connected. with strand 11 and the latter wit strand 12. The calling-plu 0 is provided with a tip 0 and-a sleeve 0 t e former bein connected with strand 13 and-the latter with strand 14. The strands 1 1 and 13 are united through condenser d and strands Y12 and 14 The levers g g of the ringin -key normally rest against contacts 1'5 and-16, respectively, and are ada ted when actuated to engage contacts 17 an 18. Contact 17 is connected through the resistance g to the grounded sideof battery 9 and contact 18 to one sideof'the callinggenerator g, which has its other-terminal carried to the active or ungrounded side of the same battery. The operators telephone set" if is adapted to be bridged between the I strands 13 14, and a condenser tf is included in circuit therewith. The relay h is connectejdfroi'n. strand -11 to round and the relay 72/ i'romi stran d 12 .to

. round and the relay 7& from strandl l to V The relay it controls contacts 19 an the relay it controls contacts 20. The 3'5 relay-contacts and'the lamp 7L3 areadapted to be included in circuit with the relay hand,

batteryCJLikewise the relay'k controls contacts'21, and the relay 7c ,controls'contacts 22.- These contacts of relays k and k are adapted to be included with lamp 7c in the circuit of battery C. pilot-relay common to all the cord-circuits of The relay h is a one operators position, and'has contacts 27 adapted to'control the circuit of the super vis'ory pilot-lamp b from battery C. The

connected with strand 13. of the cord. The' relay t is common to all of the cords of anoperators position and has contacts 26,

adapted to be included with inductioncoil winding t in' the circuit of batter 0.

Assuming that subscriber A wishes to talk to subscriber B, he lifts his telephone-receiver from the hook, thereby closin circuit of battery C through the rela l, the limbs Z Z, and the comparatively ow resistance The re' lay-Z is thus actuated and the circuit of of his receiver and transmitter.

' battery 0 completed through contacts 7,

lamp Z, and relay Z, lighting the lamp, and

thus conveying to the operator the signal attery C'. The relay 'k is connected from strand '13 to resting againstcontact 25, which isfor connection. The completion of this lamp circuit actuates relay Z", and another circuit of battery O'is completed through contacts 8, pilotlam Z and relay Z, hghting the lamp to indicate to the operator that some one of her roup of subscribers desires con 1'' not short circuited by the nection. switch-contacts 10,'the completion of the -circuit through lamp Z a ctuates the common night-bell relay Z thus closing the contacts 9 and completing the local circuit of the night= bell Z. The 0 erator upon the illumination of lamps l and 5 inserts answering-plug 1) into the'connectio'n-terminal j, belonging to line. A, and the circuit of battery 'C'is thus closedreleasing therelays Z and Z, extinguishing the lamps Z Z and interrupting-the circuit of the night-bell. The closin of contacts 1 6 and 2 5 connects the connection-terminals j to the limbs Z Z, anda circuit of battery C is completedfrom groundthroughrelay'h,

strand 12, limbs Z Z strand 11, and rela 'h' to ground. Under this condition, whic is that shown in the diagramzof Fig. -1, the circuit of lamp h remains open, for the reason that although closed at contacts 20 u on completion of the circuit through relay 'Zf 1t is interrupted at contacts 19 by the energization ofrelay h. I Theopqrator now connects her telephone set in circuit and receives. the number of the subscriber wanted, as B. She then lifts the calling-plugoand touches the tip thereof to the sleeve 7' of the connection-terminal belonging to line B. If she hears a click in her telephone, she knows that the line is busy. Otherwise, hearing no click, she will knowthat the line is idle. If the line B is connected for conversation at another board, one of the charging-batteries C or C of the cord connectors used for such connection at the'other board will be connected between ground and the sleeyes j, and consequently when the tip 0 is touched v to the sleeve y" current passes through the tigi o, strand13, spring g, and contact 15 o the ringing-key, contacts 24 and 25 of relay k, through relay t to ground. The openingv and closing of this circuit causes contacts '26 of relay t to make and break a circuit of battery C through the winding t of the operators induction-coil, thereby causin a click in her receiver, which indicates that the line is-busy. Assuming that the line is not busy, the. operator mserts,th e calling-plug in the connection-tcrmin'al belonging -to lineB, thereby sendingthecurrent of battery 0 through the relay 71- strand 14;, and thc relay 1" to ground. The

rela; 7c being thus energized the circuit of i lay 71 'being included in circuit of lamp h is lamp 7c is closed at contacts 22 and the lamp lighted. The contacts 24 and are sepa- 'line B bein rated, disconnecting the relay .t, and the contacts 23 and 24 closed, completing the circuit of cord-strand 13. The relay 1 of energized, the connection-terminals will e connected with the limbs of the-line and theline-relay Z disconnected.

ground through the circuits of batter ofbattery 'g-".., Unless'sai Eloyed', however, both relays I an Fn'fust operated b u s stance' g" to groun L, The actuation of the rmgingskey serves to o enthe strands 13 14 but as circuit is comp e'ted from battery g andgenerat'or g, through strand 14, wire 29,

and relay Z to ground, the-relay Z remains energized durin thesendi :of the callingcurrent. {The nction fof attery g is to prevent the chatterin' of the relay 1*, which would be caused by t e alternating current .from generator. 9, unless sa'id relay be specially. constructed so as to retain its armature in anattractedl'position when traversed'by alternating currents. It is "also a parent that a relay may be used at F, whic would allow its-armature to-chatter when traversed by alternating currents, but that such chattering willibe prevented by the emplo ment battery e; so constructed as to respond to and be I alternating currents. When subscriber lifts his telephone from the hookjcircuit is completed, over limbs Z Z, strand 13, and'relay k, whichfby its actuation o ens the circuit of lamp k at contacts 21, an the lamp is thus extinguished. The two subscriberstbeing now united for conversatio'n, the current from batter C asses through the instrument of subscri er' and current .from battery C passes through the instrument of subscriber-B. The'actuation of the microphoneof either subscriber causes a variation of the difference of otential at the terminals ofthe condensers (1, therebyproducin 'correspondinglyrvarying currents through t e. receiver of the other subscriber.

VVhen the subscribers have completed their conversation or in case the operators attenti'on is desired,- the hanging up of the receiver associated with the plug will light the lam which is inserte into the 'connection-ter-' minal of the line.

Thus whensubscriber A hangs 'up his receiver the circuit of battery '0 through relay h is opened and contacts The current from .19 are closed together.

. battery C continues, however, to flow from ground through rela h, strand 12 and relay 4 to v ground, and t 'ese rela s remain energized. The circuit oflamp 3 is thus closed at relays h and k lighting the lamp..' The realso energized and by its -Contacts 27 closes the circult of the supervisory pilot-lamp h lighting the same to give a'more' conspicuous signal to the o erator. The circuit of lamp k is controlle in a similar manner by the hook-switch of subscriber B, and it is evident that either subscriber may by vibrating his hook cause an intermittent lighting of the lamp associated with his line, and thus get the operators. attention. When bothsubscribers have hung up, lighting both their lamps, the operator understands this condi-.

tion as a si nal for disconnection and removes the pugs o .and .the apparatus as sumes 1ts norma condition. This description has so far referredonly to the telephonic operation of the system and is equally descriptiv'e in that res ect'of those lines which have 'the speciala arm apparatus and. of those whichare not so equipped. Referring now to this speciala paratus, the limbs ll of,

the line are carried t ou h contacts a-a of a inake-and-brealfi deg'ice h which is indicates 'agrammatica y y t e sp actuate wheel m with its stop-pin m, which normally engages the armature-lever m of ,the electr0- in c osed circuit'with the thermostats or other circuit-breaking devices f and battery :m.

The impedance I is included inpermanent fcontro led by the magnet-armature and adapted to be brought into contactwith the contacts o ai" The rela F is permanently connected from limb l o the line" to ground and has contacts controlling the continuity This electromagnet is included ofthe normally closed circuit of batterym. 4

Theregister 'or recording device, which may be an ordinary telegraph-register, is indicated at R and has astop' r, which is normally engaged by the releasin -arm r until. released y the retraction of the armature .Of the-electroma etrh. The recording-point rfis also 1s spring-actuated wheel r and itstape or ribbondn'responseto the retraction of the armature. Switch-contacts 30 are provided adapted to be closed the first re-traction of the magnet-armature to complete the circuit of battery 1' through lamp r" and to remain closed without interfering with subsequent movements of the armature until manually separated. It will be seen that when a plug is inserted the relay F is in shuntwith rela j ustment of relay F is required, it is desirable that a corresponding shunt be maintained at all other times, and the resistance 1" is shown connected to indicate thatsuch a connection -may be made. to e ualize the currentflow through relay F or or other balancing purposes. ,Theampedance' of the coil I is sufii- ,W'hen an especiallyssensitive a tery C is closed fromf Io relay 1, thelimbs Z Z,

' times.

5 limb l 7/ should become groun rent" has sufficiently high resistance to prevent a flowof current which would attract or hold u the armatures of the relaysl, h or k L T e relay F is so wound and ad- 5 justed that its armature will be held attracted at all' times, e'xce t when. there is a comlete interruptiono current in the limb l. nder normal conditions the, circuit of bat- .%o'und through the t e contacts-c of, the coilI, and the relay F to ound, The currentunder this condition 1s not of sufiicient strength to 'actuaterela 1 but, does hold the armature'of rela F. en subscriber A re- 5 moves his telep one from the hook-switch,

I this current is increased in volume and the armature of'relay F remains attracted. In

case the operator-,actuates her ringing-key to call a subscriber there is a circuit of genera- 2 tor g' and battery g'i completedfrom round ;through strand 14, impedance I,--lim 5 Z 1',

and relay F to ground, and owing tothe nature of'its construction the relay is energized by-this calling-current to hold its armature 2 5 attracted. The normal condition is indicated in the diagram of line A. v. The diagram of lineB shows the alarm apparatus in o eration. Here the circuit of battery m? an electromagnet 'm has been broken at the device f.

It is to be understood that thespring v of the Inake-and-break wheel m; is normally undertension, When thecircuit of magnet m is opened, it ceases to attract itsarmaturerlever m which being retracted by the srin m .disen a es the sto m and allows t e w eel v g a P 'm; to revolve a predetermined number of As it revolves the projections on its periphery engage the part a, controlling contacts ac, and the circuit of relay F is thus interrupted to correspondwith such projections. At the first interruption the circuit of the register-magnetr is broken at contacts 31 of magnet F, and its armature engages and.

closes the contacts 30, thus completing the 4 5 circuit of battery 1" through lamp 1. I At the same time the tape-wheel r is released by the arm T, and the number and sequence of the interruptions is recorded in the Wellknown manner by'the point r .becomes broken or open the consequent deenergization of rel ay F will result in li hting the lamp 1, and theregister will recor a'contin- 'uous interruption. Likewisegi in case either to interfere with the desired operation of relay F the contacts will be separated and give a similar indication; In this Fi 1 diagram,

as in the subsequent drawings, w ere the vari- "6o ous ground connections for the telephonic apparatus are shown, it is to be understood that these round connections represent the common .oiiice return or a direct connection to the rounded terminals of the main batteries C .0. The ground connection of relay It may be 5 c readily seen that in case either limb of the line ed to an extent F ma X be the same central-office ground or may e aground at some other point, asis most desirable. that current for the circuits -of the various minor central-office batteries, as 'r, g and others, may be su plied from one of the main batteries 0 C, if desired. The make-andbreak device l\1 and the recording device R are only intended as diagrammatic illustra tions for' pur ose'of description of devices which fi'lw'i ol and well known Without regard to their specific mechanical construction. It will be seen from this description that the operation of the alarm a'pparatusis not at anytime interfered with in the use of the telephonic apparatus. There is nor- It is also to be understood,

mally a comparativel weak current flowing to attract its armature. When this current is increased in volume the removal of the. receiver from the hook-switch, the armature is still attracted. When the operator by through limbs Zilf an relay F, which sufiices" plugg'ing'into a line substitutes the battery I connections of the cord for those of the line, a sufi'icient current-flow is' still maintained. The relay F is of such con structionthat when rin' ing-current is put on the line its armature wil be attracted by this current. any of these conditions an alarm-signal is to be transmitted, the opening of contacts a a If under' deprives therelay'F ofall current, and its contacts separate, thus controlling the other receiving apparatus and indicating an alarm.

. Fig. 2 shows an alternative arrangement of.

the substation apparatus. Inthis figure the condenser s and impedance I are omitted; but a high resistance 8 is included in the bridge with the bell s. This bell, while not of veryhigh resistance, has suflicient impedance to prevent undue shunting of voice-currents, and the resistance, which may be a part of the winding of the bell-magnets or exterior thereto, is included in the bell-bridge to reduce the normal direct current-flow to a point where it will not interfere with the action of the telephone-relay.

Fig. 2 indicates an arrangement of the alarm-sending apparatus similar to that of' 'Fig. 1 except that the make-and-break device is controlled by, means of a normally open circuit. In this arrangement a thermostat or other circuit-controllin device is shown at f, in which its termin'a sare normally not connected. Upon its operation, as by heat, its terminals become connected and complete the circuit of battery m through In agnet in thu s attracting armaturelever m This (lisenga es the stop m and,allows the Wheel to revo 've and transmit the alarm-si nal over the limbs Z Z in the manner previously-described.

Fig. 2 shows an arrangement'of the al armsendi ng apparatus in whlch the contacts a a of the make-and-break device M are directly controlled by a relay in the 'l'o'c'ai circuit. In

A Under the action of heat this piece by fusing transmit/the signal, as before.

I if desired, and the corresponding limb made der tension it is held in the normal position shown by a piece of fusible metal or other heat-responsive device, (indicated at f.)

or otherwise releases the wheel, which re v olving a predetermined number of tunes breaksand'makes the circuit of battery m at contacts a in accordance with the projec-' tions on its periphe The armature of relay m is consequent released each time the circuit is broken an controls the contacts\ a it to correspond with the characteristic interruptions of the device M This transmits the signal over the limbs Z l to the receivingstation, as hereinbeforedescribed.

Fig. 2 shows asimilar arrangement to that shown in Fig. 2, except that the circuitof battery m and relay m is normally open instead of being normally closed. In thiscase the device M WhGIL released closes the circuit, of battery'm throughrelay m and-contacts a and at each time of closing the magnet m? being energized opens the contacts a a to Fi 2 illustrates an arrangement in whic the contacts a a of the line-limbs l l 'are'directly controlled b associated with the make-and-break wheel m and are includedin the limbs Z 1 intermediate of the bridged impedance I and'the alarmreceiving apparatus. When the wheel is re leased under the influence of heat, the con tacts an are open and closed to ive the charate ristic signal, -as hereinbe ore explained. v l Fig. 2' shows an arrangement in which the inakc-antkbreak-devioe M might be said to correspond to the regular distrlct messengerbox. The limbs 11 are carriedthrough the contacts a a and thence to the bridged imhe wheel m when actuated (in the diagram by de'pressingthe lever m?) breaks and makes the contacts a a in the manner to transmit the characteristic alarm-signal. v

While the foregoing .dia rams, as well as subsequent ones','1ndicate t at a contact a or a is included in each limb Z l of theline, it is I obvious-that one contact might be omitted,

permanently continuous at that point with out interfering with the operativen'ess ofthe system;

Fig. 3 indicates an alternative arrangement of the alarm-receiving device to that assess the thermostatic .deviceM In this case t e contacts a, a, are

until extinguished shownin Fig. 1. In this arrangement the circuit of battery 1", which includes the register magnet T is normally open at contacts 31 of the relay F. In receiving a signal these contacts are closed at each interruption of current in the relay F 3 the magnet Wis cone-- spondingl energized, and attracting its annature 1'" re eases the wheel r and records th signals in the Well-known manner. 1

In, Fig. 4; and s bsequent drawings the recording device is indicated by a simple conventional diagram at R, and it is to be un-. derstocd that this device may be any aprover] type of telegraph-register orequ1va- 'enr mechanism. In Figs. 1 and 3 it has been assumed that the register R is individual to the line of relay Fin other words, that each telephone-line using the special alarm apparatus has a separate register. Fig. 4 shows the individual register arrangement of. Fig. 3 in association with an individual pilot-lamp. The circuit of battery 'r through register R is normallyop'en at contacts 31 and includes a winding b of the relayb. This relay has another winding b in circuit with lamp b, .and battery r, terminating at the normally open cpntact b. There'is an armature-contact I connected throu' h the contact of key I) to the other side of attery r ing 1) is subsequently broken at cont acts 31,

current through winding]; will continue to energize the relay 1) and maintain the circuit of the lamp closed until it is momentarily broken by the operator at key b", after winch the circuit will assume its normal condition. By this arrangement the pilot-lamp b is lighted in response to the first movement of the armature of rela F and remains lighted y the alarm operator,

indication. I

Fig. 5 shows'an arrangement of. an ndividual register and pilot-lamp, the register being in a normal] closed circuit. In this figure a circuit 0 battery 1" is normally closed through the winding-of the electro- -magnet b, the register'R, and contacts 31.

This magnet?) carries on itsarmature a catch 1), which normally engages a corresponding catch on' the contact iece b. This contact-piece is connecte through lam b to. one' side of battery r and is adapted w en releasedlto engage contact I), which is connected to the other side of the battery. When contacts 31 are separated, as in response to an alarm-signal, the magnet b is thus d energized and its armature retracted, releaslng the contact-piece b, which engages contact 7 When contacts 31 are closed in response to an alarm-s1gnal thus giving him a special and conspicuous;-

b thus completing the circuit of lamp and The contact-piece 6 W111 remain in its released. position until lig ting the same.

I. manually-restored, and the pilot-lam b will fthus remainlighted and be unaffecte by any subsequent movement of contacts 31 until the attention of the operator is attaracted. Fig. 6 indicates means'difl'erent from that In this ar- 'jtactb, from; contact. 1;", therelay-winding,

* closed at contacts 31 (an in receivin .contacts 5'3 63'and has also a catch 1), normally engages contact-pieceb.. This of the battery. The contact-piece will and 'contacts31. As lon as this circuit 1s consequentl the circuit a of registerR) relay b is energize and attracts its armaturefcontact to engage contact-b. Whencontacts'31 are separated as a si nal, the circuit of relay is interrupts an .its armature-s ring breaks contact b1 and engages contact ,comp'let: I

b and battery 1".

in the circuit of pilot-lam bsequent movement 0 contacts31, while sti'llJ ontrolling the register, willrn'ot afli'ect the-1'- ayfi', for the reason that its circuitinow stands-open at I contact bf? and'the pilot-lamp will continue to burn until extinguished by the manual restoration of armature-contact f b to its normal position.

Fig. 7 indicatesan arrangement in which the register R is common to two or more lines, each line being provided with an indi-" vidual pilot lamp. In this arrangement each line has a relay. I) inserted in circuit with battery 1" and contacts 31, which stand normally open. The relayarmature controls which contact-piece is connected with battery 1' and'is adapted when released to drop forward and engage contact 43, which is cone nectedthrough lam'p b? to the opposite side remain in its released positt-ion until manually restored. The contacts 53 of the relays b of all lines which'utilize thesame'register are connectedto'one side of the vbatt'e ryvfl'and the contacts 63 of all of these relays are connected through the register. to the o .osite side of the battery. A switch b-is-in icated for each line, by which aline-circuit may bedisconnected from the eo'mmon; register in case fof trouble on lines-toas iii-receiving asignal, completes a circuit of battery rr.through relay b; and its armature being attraeterlreleases contact-piece b3, and thus closes. the pilot-lamp circuit, lighting:

the lamp. ,Atthe same time the relay 6 acting in'rea'panse to the intermittent closing of reyent interfer ence with the operation-o the register by other lines. The first motionof contacts 31,

its circuit at contacts 31 .operates the register R by closing its common circuit. at contacts 53. 63. While this arrangement, as well as those of Figs. 8 and 12 following, has the disadvantage of .a ossible interference in case two alarm-sign'as are received at the same time, it makes it possible to arrange the a paratus in a compact manner and reduces t e amount of a paratus required.

"Fig. 8 in lcates a closed-circuit arrangemept of the individual pilot-lamp with a common register. Here the circuit of relay b and battery r is normally closed'at contacts 31, and by the attraction of' its armature the catch b engages contact-piece b. 1 The contacts 53 63 of each relay form normally open terminals of the circuit of register R and battery 1". Whenthe circuit of relay b is opened at contacts-'31, as in receiving a signal,'- the consequent retraction of the relay armature releases contact-piece 6 allowing it to fall forward and complete the circuit of lamp b through battery 1 and contact 43. The lamp then remains lighted until the con-v 'tact-piece b is restored by the operator. The relay balso closes contact 53 63 at each interruption of its circuit, and thus controls the register R in the regular ma nner.

- .Fig.'9 illustrates a closed-circuit arrangement for individual register and pilot lamp somewhat similar to that of Fig. 6. In tlus system the relay 1) instead of'being in shunt 'of the register R is in a separate circuit of battery 1" and is controlled by an extra pair of contacts 32 on relay F. The operation is similar tothat of Fig; 6.

Fig. 10 shows an open-circuit arrangement forindividual register and pilot-lamp in which there is an extra pair of contacts 32 on relay .F for controlling the lamp. 'In this arrangement contacts 31 control the register, as before. At the same time when contacts 32' are first closed a circuit of battery. 1" is completed through relay b and resistance 1), en

jergizing the relaybiand' closing its contacts.

A circuit of battery 'r is thus completed through relay 7), contacts 45 55,- key I), and lamp 1), and it is obvious that'the lamp willv remain permanently lighted untilthis circuit is broken at contact 62 of. key I). sistance b is provided to prevent the circuit through contacts 32 from shortcircuiting the lamp after it is lighted.

I Fig. 1.1indicates'the use of an individual register foreach line, which may be in a normally open or closed circuit, as desired,

here shown in a normally. closed circuit.

A registerR is also shown as .commonate a 'roo I part or all of the lines and is controlled by an-extra pair of contacts 32 on each of the relays F in the usual manner". that the common register R mi ght be included in a' normally closed circuit by including all of the c ma-0mm of all of the group of relays F serially in the circuit of this register,

I7": It isobvious;

2 5 undue impedance to voice-currents.

13 the active winding w has a parallel or twin seemed necessary to illustrate such modifica- .cuit pilot-lamp arrangement of Fig. 10 could tions by separate drawings, and this will also apply to the next figure.

- ig. 12 indicates a common register controlled by one pair of contacts 32 in combination with an individualpilot-lamp controlled. by another pair'of contacts 33. The pilotlamp circuit is the closed-circuit arrangement of Fig. 9, the nature and operation of which ,has'been made clear in the foregoing d 'escriptions'. It is apparent that the open-cirbe substituted for that shown in this figure by the use of a back contact for vthe relay In the foregoing drawings, Figs. 3 to 12, inclusive, it is assumed that the relay F is associ atedgwith limb I 1 or of the line, as indicated in this application.

Figs. 13 to 18, inclusive, indicate diagram matically well-known rnethods of arrangement for relay F, by which it may be serially included in the line-limbs without presenting In Fig.

winding '0, the ends of which are connected together or short-circuited. In Fig. 14 the active winding is shunted by a winding of higher resistance 1)., having substantially the same number of turns, but connected in opposition thereto, so that current in one winding opposes that in the other.

In Fig. 15 the core a: of the relay-magnet is inclosed in a shell 4 of copper or other non-magnetic metal. In Fig. 16 the active winding whas a permanent shunt 'v of non-inductive resistance, and in Fig. 17' this shunt-path includes contacts 71 72 of the relay, which engIage afn Fig. 18 the Win ing w is permanently bridged by the condenser 1 In the drawings where the relay F is serially in the talking-circuit of the telephoneline it has only been indicated conventionany, audit is to be understood, as indicated,

' that the relay is so arranged as to present no .undue interference or impedance to the telephonic currents. r I

- Fig. 19 illustrates my invention as embodied in an exchange system of the three-wire gype. o The line-circuit A differs from that of 1' only in that the connection -terminals I j have two line-springs permanently connected to the limbs l l" and a sleeve or test-thimble 1, which ins-connected by a local-circuit vwire with the cut-oil relay '1.

Two cord-circults ordinarily used in such a system are shown at D arid-E. Th at at D differs from' .the cord-circuit of Fi 1 with regard, to structure but in genera results its operation, as will be seen, is the same. Insteadof uniting thc-cord-strands '11 '13 and 12 14 by cn densers they are inductively related by the the line-lamp Z.

'associate 7 moving his receiver from its hook, .thuS-cempleting a low-resistance path :in circuitof .ba't- 7 tery Cthrough the line relay lf, .li ghting-;the lamp Z, The operator by the insertion of. the answering plug p completes the local circuit of batteryC from ground through resistance 7", lamp h", ilug-contact p, thimble 8c v 7' and cut- 6H relay to ground, eneiigizi the relay to disconnect the line-relay v aiig (when used) the resistance r, extinguishing The subscri'bers circuit is. now completed from round through battery 8 5 C repeating-coil win in 2", relay h, strand 12, contact 1), spring 7', imbs Z 1, spring 9, contact p, stran'd 11, and winding '1 to ground. Inithe o eration of thetransmitter the resistance of t 's circuitis varied in ac- 9o cordance with the voice-vibrations, and the current-flow through windin s 1 2 of the repeating-coilvaries according y. This varia ti on in current induces alternating currentsm windings 3 4; of corresponding value, and 95 thus ener izes the'receiver of the subscriber with the callin '-plug 0. As

as circuit is closed throng the hook-switc contacts 8 s relay hv is energized and by its contacts 51 6 1 completes .a circuit in 10: shunt of lamp l't throu h the lowresistance 8, keeping the lamp ark. As soon, however, as the receiver is replaced, the'contacts of relay h separate, the lamp 1 receives the full current in'the circuit of-relay Z previously 105 traced and becomes lighted. In making a busy test it is'obviousthat under normal conditions the touching of tip 9 to a thimble will not afiect the operator's receiver. If,

owever, this thimble is connected to .the :10 active terminal of battery C? throu h the local circuit of the cord, which inclu es resistance 7 it is evident wlJ at when the test is made there will be a flow of current fromthe thimble j throu h tip 0', strand 13, andiwmd- 1 ing 3 to grdumi This flow will, change-the potential at the terminals of condenser t and cause the busy click in the .operators receiver in a manner well understood. Theoperator listens and 'ringsin the usual- I'nanr ner, and the circuits under such conditions are evident'from the drawi. s.- When both subscribers have hung up, the 'ghti of their corresponding cord-'lampsprovides .t eusual disconnect signal. Whennecessary, thelini- Z1: 5 pedance-c'oil 1 maybe connected between'batcircuit E of Fig. 19 operates infsubs tantially (r3 

